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  1. Artikel: High power illumination system for uniform, isotropic and real time controlled irradiance in photoactivated processes research.

    Sáenz, Carlos / Hernández, Begoña / Sanz-Carrillo, Diego / Pellejero, Ismael / Gandía, Luis M

    Heliyon

    2024  Band 10, Heft 10, Seite(n) e31309

    Abstract: In the study of photocatalytic and photoactivated processes and devices a tight control on the illumination conditions is mandatory. The practical challenges in the determination of the necessary photonic quantities pose serious difficulties in the ... ...

    Abstract In the study of photocatalytic and photoactivated processes and devices a tight control on the illumination conditions is mandatory. The practical challenges in the determination of the necessary photonic quantities pose serious difficulties in the characterization of catalytic performance and reactor designs and configurations, compromising an effective comparison between different experiments. To overcome these limitations, we have designed and constructed a new illumination system based in the concept of the integrating sphere (IS). The system provides uniform and isotropic illumination on the sample, either in batch or continuous flow modes, being these characteristics independent of the sample geometry. It allows direct, non-contact and real time determination of the photonic quantities as well as versatile control on the irradiance values and its spectral characteristics. It can be also scaled up to admit samples of different sizes without affecting its operational behaviour. The performance of the IS system has been determined in comparison with a second illumination system, mounted on an optical bench, that provides quasi-parallel beam (QPB) nearly uniform illumination in tightly controlled conditions. System performance is studied using three sample geometries: a standard quartz cuvette, a thin straight tube and a microreactor by means of potassium ferrioxalate actinometry. Results indicate that the illumination geometry and the angular distribution of the incoming light greatly affect the absorption at the sample. The sample light absorption efficiency can be obtained with statistical uncertainties of about 3% and in very good agreement with theoretical estimations.
    Sprache Englisch
    Erscheinungsdatum 2024-05-20
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 2835763-2
    ISSN 2405-8440
    ISSN 2405-8440
    DOI 10.1016/j.heliyon.2024.e31309
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  2. Artikel: Study of Recycling Potential of FFP2 Face Masks and Characterization of the Plastic Mix-Material Obtained. A Way of Reducing Waste in Times of Covid-19.

    Crespo, Cristina / Ibarz, Gemma / Sáenz, Carlos / Gonzalez, Pablo / Roche, Sandra

    Waste and biomass valorization

    2021  Band 12, Heft 12, Seite(n) 6423–6432

    Sprache Englisch
    Erscheinungsdatum 2021-05-31
    Erscheinungsland Netherlands
    Dokumenttyp Journal Article
    ZDB-ID 2541900-6
    ISSN 1877-265X ; 1877-2641
    ISSN (online) 1877-265X
    ISSN 1877-2641
    DOI 10.1007/s12649-021-01476-0
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  3. Artikel: Study of Recycling Potential of FFP2 Face Masks and Characterization of the Plastic Mix-Material Obtained. A Way of Reducing Waste in Times of Covid-19

    Crespo, Cristina / Ibarz, Gemma / Sáenz, Carlos / Gonzalez, Pablo / Roche, Sandra

    Waste and biomass valorization. 2021 Dec., v. 12, no. 12

    2021  

    Abstract: The purpose of this study is to investigate how to recycle FFP2 face masks used during Covid-19 pandemic without using previous sorting process and to characterize the properties of the material obtained. The way of splitting and processing the mixture ... ...

    Abstract The purpose of this study is to investigate how to recycle FFP2 face masks used during Covid-19 pandemic without using previous sorting process and to characterize the properties of the material obtained. The way of splitting and processing the mixture of materials was studied as well as the final properties such as chemical, thermal and mechanical characteristics. The resulting recycled material is a blend of polymers with such mechanical and thermal properties that could be used as an alternative to recycled PP (polypropylene). Avoidance of previous sorting process gives the face mask recycling a new and simplified way of preventing this material to be disposed in environment and an opportunity of second life for the polymers they are made of. With this work we lay the basis to reduce the plastic pollution related with the recommended use of face masks during Covid-19 pandemic.
    Schlagwörter COVID-19 infection ; biomass ; face ; face masks ; pollution ; polypropylenes ; wastes
    Sprache Englisch
    Erscheinungsverlauf 2021-12
    Umfang p. 6423-6432.
    Erscheinungsort Springer Netherlands
    Dokumenttyp Artikel
    ZDB-ID 2541900-6
    ISSN 1877-265X ; 1877-2641
    ISSN (online) 1877-265X
    ISSN 1877-2641
    DOI 10.1007/s12649-021-01476-0
    Datenquelle NAL Katalog (AGRICOLA)

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  4. Artikel: Diffuse irradiance on tilted planes in urban environments: Evaluation of models modified with sky and circumsolar view factors

    García, Ignacio / de Blas, Marian / Hernández, Begoña / Sáenz, Carlos / Torres, José Luis

    Renewable energy. 2021 Dec., v. 180

    2021  

    Abstract: Numerous studies have analyzed existing irradiance models for estimating sky diffuse irradiance on tilted planes. However, few have evaluated the suitability of these models for estimating irradiance in obstructed environments, specifically considering ... ...

    Abstract Numerous studies have analyzed existing irradiance models for estimating sky diffuse irradiance on tilted planes. However, few have evaluated the suitability of these models for estimating irradiance in obstructed environments, specifically considering the effects of obstacles. In this study, three irradiance models —one of them with five variants— for estimating diffuse irradiance on tilted planes located in urban environments were evaluated. All models have been adapted to consider the effect of an urban canyon on the diffuse irradiance received on a tilted plane through the sky view factor and the circumsolar view factor. All the models were evaluated against the diffuse irradiance values obtained by the ISO 15469:2004(E)/CIE S 011/E:2003 angular distribution model. Therefore, it was necessary to determine the standard sky type corresponding to each record of the measurements performed by a sky scanner at the radiometric station of UPNA (Spain). A total of 4,864 scenarios were considered to occur from the combination of different orientations and inclinations of the plane, and different orientations and aspect ratios of the urban canyon. The results revealed that the Perez model considering a 35° half-angle circumsolar region has the best performance, followed by the Perez model considering a 45° half-angle circumsolar region.
    Schlagwörter light intensity ; models ; radiometry ; renewable energy sources ; scanners ; Spain
    Sprache Englisch
    Erscheinungsverlauf 2021-12
    Umfang p. 1194-1209.
    Erscheinungsort Elsevier Ltd
    Dokumenttyp Artikel
    ZDB-ID 2001449-1
    ISSN 1879-0682 ; 0960-1481
    ISSN (online) 1879-0682
    ISSN 0960-1481
    DOI 10.1016/j.renene.2021.08.042
    Datenquelle NAL Katalog (AGRICOLA)

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  5. Artikel: Comparative Analysis of SARS-CoV-2 Antibody Responses across Global and Lesser-Studied Vaccines.

    Zambrana, José Victor / Saenz, Carlos / Maier, Hannah E / Brenes, Mayling / Nuñez, Andrea / Matamoros, Anita / Hernández, Mabel / Dumas, Keyla / Toledo, Cristhian / Peralta, Leonardo / Gordon, Aubree / Balmaseda, Angel

    Vaccines

    2024  Band 12, Heft 3

    Abstract: Few data are available on antibody response for some SARS-CoV-2 vaccines, and there is a lack of ability to compare vaccine responses in the same population. This cross-sectional study conducted in Nicaragua examines the SARS-CoV-2 antibody responses in ... ...

    Abstract Few data are available on antibody response for some SARS-CoV-2 vaccines, and there is a lack of ability to compare vaccine responses in the same population. This cross-sectional study conducted in Nicaragua examines the SARS-CoV-2 antibody responses in individuals, previously exposed to high infection rates who have received various vaccines. The vaccines under comparison include well-known ones like Pfizer (BNT162b2) and AstraZeneca (ChAdOx1-S), alongside less-studied vaccines including Soberana (Soberana 02), Abdala (CIGB-66), and Sputnik V/Sputnik Light. Overall, 3195 individuals participated, with 2862 vaccinated and 333 unvaccinated. We found that 95% of the unvaccinated were seropositive, with much lower titers than the vaccinated. Among the vaccinated, we found that Soberana recipients mounted the highest anti-spike response (mean difference (MD) = 36,498.8 [20,312.2, 52,685.5]), followed by Abdala (MD = 25,889.9 [10,884.1, 40,895.7]), BNT162b2 (MD = 12,967.2 [7543.7, 18,390.8]) and Sputnik with AstraZeneca as the reference group, adjusting for age, sex, vaccine status, days after last dose, and self-reported COVID-19. In addition, we found that subjects with complete vaccination series had higher antibody magnitude than those with incomplete series. Overall, we found no evidence of waning in the antibody magnitude across vaccines. Our study supports the conclusion that populations with high infection rates still benefit substantially from vaccination.
    Sprache Englisch
    Erscheinungsdatum 2024-03-19
    Erscheinungsland Switzerland
    Dokumenttyp Journal Article
    ZDB-ID 2703319-3
    ISSN 2076-393X
    ISSN 2076-393X
    DOI 10.3390/vaccines12030326
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  6. Buch ; Online: Analysis of the influence of political polarization in the vaccination stance

    Ebeling, Régis / Sáenz, Carlos Abel Córdova / Nobre, Jeferson / Becker, Karin

    the Brazilian COVID-19 scenario

    2021  

    Abstract: The outbreak of COVID-19 had a huge global impact, and non-scientific beliefs and political polarization have significantly influenced the population's behavior. In this context, COVID vaccines were made available in an unprecedented time, but a high ... ...

    Abstract The outbreak of COVID-19 had a huge global impact, and non-scientific beliefs and political polarization have significantly influenced the population's behavior. In this context, COVID vaccines were made available in an unprecedented time, but a high level of hesitance has been observed that can undermine community immunization. Traditionally, anti-vaccination attitudes are more related to conspiratorial thinking rather than political bias. In Brazil, a country with an exemplar tradition in large-scale vaccination programs, all COVID-related topics have also been discussed under a strong political bias. In this paper, we use a multidimensional analysis framework to understand if anti/pro-vaccination stances expressed by Brazilians in social media are influenced by political polarization. The analysis framework incorporates techniques to automatically infer from users their political orientation, topic modeling to discover their concerns, network analysis to characterize their social behavior, and the characterization of information sources and external influence. Our main findings confirm that anti/pro stances are biased by political polarization, right and left, respectively. While a significant proportion of pro-vaxxers display haste for an immunization program and criticize the government's actions, the anti-vaxxers distrust a vaccine developed in a record time. Anti-vaccination stance is also related to prejudice against China (anti-sinovaxxers), revealing conspiratorial theories related to communism. All groups display an "echo chamber behavior, revealing they are not open to distinct views.

    Comment: Accepted for the AAAI 16th International Conference on Web and Social Media (ICWSM 2022), and to be published in the ICWSM 2022 Proceedings. Please, cite the proceedings
    Schlagwörter Computer Science - Social and Information Networks
    Erscheinungsdatum 2021-10-07
    Erscheinungsland us
    Dokumenttyp Buch ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  7. Buch ; Online: On Requirements for Programming Exercises from an E-learning Perspective

    Loria-Saenz, Carlos

    2009  

    Abstract: In this work, we deal with the question of modeling programming exercises for novices pointing to an e-learning scenario. Our purpose is to identify basic requirements, raise some key questions and propose potential answers from a conceptual perspective. ...

    Abstract In this work, we deal with the question of modeling programming exercises for novices pointing to an e-learning scenario. Our purpose is to identify basic requirements, raise some key questions and propose potential answers from a conceptual perspective. Presented as a general picture, we hypothetically situate our work in a general context where e-learning instructional material needs to be adapted to form part of an introductory Computer Science (CS) e-learning course at the CS1-level. Meant is a potential course which aims at improving novices skills and knowledge on the essentials of programming by using e-learning based approaches in connection (at least conceptually) with a general host framework like Activemath (www.activemath.org). Our elaboration covers contextual and, particularly, cognitive elements preparing the terrain for eventual research stages in a derived project, as indicated. We concentrate our main efforts on reasoning mechanisms about exercise complexity that can eventually offer tool support for the task of exercise authoring. We base our requirements analysis on our own perception of the exercise subsystem provided by Activemath especially within the domain reasoner area. We enrich the analysis by bringing to the discussion several relevant contextual elements from the CS1 courses, its definition and implementation. Concerning cognitive models and exercises, we build upon the principles of Bloom's Taxonomy as a relatively standardized basis and use them as a framework for study and analysis of complexity in basic programming exercises. Our analysis includes requirements for the domain reasoner which are necessary for the exercise analysis. We propose for such a purpose a three-layered conceptual model considering exercise evaluation, programming and metaprogramming.

    Comment: ii + 31 pages
    Schlagwörter Computer Science - Artificial Intelligence
    Thema/Rubrik (Code) 004
    Erscheinungsdatum 2009-03-04
    Erscheinungsland us
    Dokumenttyp Buch ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  8. Buch ; Online ; Dissertation / Habilitation: Influence of spectral fine structure on the electronic transport of icosahedral quasicrystals

    Landauro Sáenz, Carlos V

    2002  

    Verfasserangabe vorgelegt von Carlos V. Landauro Saenz
    Schlagwörter Quasikristall ; Elektronischer Transport ; Transportkoeffizient ; Ab-initio-Rechnung ; Übergangsmetall
    Sprache Englisch
    Umfang Online-Ressource
    Dokumenttyp Buch ; Online ; Dissertation / Habilitation
    Dissertation / Habilitation Techn. Univ., Diss--Chemnitz, 2002
    Datenquelle Ehemaliges Sondersammelgebiet Küsten- und Hochseefischerei

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  9. Buch: On requirements for programming exercises from an e-learning perspective

    Loría-Sáenz, Carlos

    (SEKI working paper ; 2008,1)

    2008  

    Verfasserangabe Carlos Loría-Sáenz. Universität des Saarlandes, Fachrichtung Informatik
    Serientitel SEKI working paper ; 2008,1
    Sprache Englisch
    Umfang 31 S., graph. Darst., 30 cm
    Verlag Univ., Fachrichtung Informatik
    Erscheinungsort Saarbrücken
    Dokumenttyp Buch
    Anmerkung Literaturverz. S. 28 - 31
    Datenquelle Katalog der Technische Informationsbibliothek Hannover

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  10. Konferenzbeitrag: Headless screws versus Bouquet in intramedullary fixation in unstable neck metacarpal fractures in active patients: a randomized study

    Aita, Marcio Aurelio / Kaempf De Oliveira, Ricardo / Ruggiero, Gustavo Mantovani / Biondi, Bruno / Eduardo Saenz, Carlos / Delgado, Pedro J.

    2020  , Seite(n) IFSSH19–675

    Veranstaltung/Kongress 14th Triennial Congress of the International Federation of Societies for Surgery of the Hand (IFSSH), 11th Triennial Congress of the International Federation of Societies for Hand Therapy (IFSHT), 11th Triennial Congress of the International Federation of Societies for Hand Therapy (IFSHT); Berlin; ; International Federation of Societies for Hand Therapy; 2019
    Schlagwörter Medizin, Gesundheit ; boxer's fractures ; metacarpals fracture ; cannulated screws ; minimal invasive ; intramedullary fixation ; surgical treatment ; randomized trial
    Erscheinungsdatum 2020-02-06
    Verlag German Medical Science GMS Publishing House; Düsseldorf
    Dokumenttyp Konferenzbeitrag
    DOI 10.3205/19ifssh0788
    Datenquelle German Medical Science

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